1. FIELD OF THE INVENTION
The present invention relates to a color photographic light-sensitive material and, more particularly, to a diffusion transfer color photographic material which provides simultaneously both a positive image and a negative fixed image having improved gradation.
2. DESCRIPTION OF THE PRIOR ART
The so-called diffusion transfer color photography, in which a silver halide emulsion layer is used as a light-sensitive element and diffusible dyes formed as a result of the imagewise exposure and development are allowed to diffuse in an imagewise manner into another layer and are fixed there to form dye images, is well known. In this photographic process, since transferred dye images are formed in a layer different from the emulsion layer, it is not necessary to remove remaining emulsion particles and silver deposited by fixing, bleaching or like steps. Therefore, dye images can be obtained using only one processing.
Known systems of providing diffusion transferred dye images include a process of using a compound capable of reacting with an oxidation product of an aromatic primary amino developing agent to release a diffusible dye, and a number of processes for obtaining diffusible dyes with a positive distribution using a negative type light-sensitive silver halide emulsion. Furthermore, the transfer of dye images from a light-sensitive element comprising a support having superposed thereon a plurality of emulsion layers having associated therewith diffusible dye-providing materials for subtractive color reproduction to a common image-receiving layer is also known.
However, the conventionally known diffusion transfer color photographic materials are so designed that only one dye image (positive type in many cases) is formed by transfer and the processed light-sensitive element is not further used or is thrown away.
In this respect, Japanese patent application No. 61122/73 discloses a film unit which contains a unit comprising:
1. a negative type silver halide emulsion layer containing a non-diffusible coupler capable of reacting with an oxidation product of an aromatic primary amino developing agent to provide a non-diffusible dye and a diffusible development inhibitor, and
2. an adjacent light-insensitive layer containing a diffusion-resistant coupler capable of reacting with an oxidation product of an aromatic primary amino developing agent to provide a diffusible dye. The above-described unit has enabled one diffusion transferred positive image and one negative image comprising non-diffusible dye which can be used as a color print original to be obtained.